This invention relates to a multi-color transfer image forming method to be used for formation of color proof, etc.
In carrying out color printing, in either of lithography, letter press or gravure, the half tone method is used, and color-resolved dots, positive or negative plate is required.
For saving of labor and time for proofreading performed prior to such practical printing, a color sheet for proofreading, namely color proof, has been generally known.
Concerning layer constitution and image forming method for such color proof, various proposals have been made. Typical transfer system of color proof are (1) the method in which a colored image is formed by transferring a photosensitive layer containing a colorant onto a support and repeating exposure and developing; (2) the method in which a photosensitive tacky layer is laminated onto a support and a toner is applied after exposure; and (3) the method in which monochromatic images formed on a color sheet are successively transferred onto an image receiving layer, and retransferred onto an image receiving member.
However, the above respective methods are complicated in process and require enormous labors. Also, particularly the colored image layer transferred, partly because it takes the form embedded in the receiving layer in the method of (3), had luster not only on the surface of the transferred image but also on the non-image portion, and therefore gave a feeling of quality or image quality different from practical printed matter. Accordingly, in order to make the image quality approximate to that of practical printed matter as possible, the transferred image surface is required to be subjected to matting treatment, and even if such treatment may be effected, the feeling of quality given was different from that of practical printed matter.